The VTU-6125C4 from Communications & Power Industries is a Traveling Wave Tube with Frequency 13.75 to 14.5 GHz, Power 125 kW, Gain 50 dB, Collector Voltage 4.2 to 5 kV (DC), Cathode Current 170 mA(DC). Tags: Helix. More details for VTU-6125C4 can be seen below.